PHY 101 - Meeting #10

Topic(s)
  • The early atom (selected topics)
  • The modern atom
Reading List Pages 482-496, 498-523
Objectives
  • Be able to describe how blackbody radiation is created.
  • Understand that it is the radiation that we discussed back in the chapter on heat transfer as "radiation".
  • Know how the classical description of blackbody radiation failed.
  • Be able to describe in very general terms how Planck was able to properly explain blackbody radiation.
  • Discuss what is meant by a "quantum" of energy
  • Be able to thoroughly discuss the photoelectric effect and its explanation.
  • Be able to discuss the dual nature of light (i.e. particle or wave)
  • Why was Rutherford's model of the atom replaced by Bohr's
  • Realize that Bohr's model of the atom predicted quantized orbits and quantized energy which allowed spectra to be explained
  • Understand that x-rays are electromagnetic waves (or photons if you prefer) that are generated when charges undergo very large accelerations.
  • Compare and contrast x-rays and light rays
  • Be able to discuss some of the failures of the early models of the atom
  • Be able to discuss deBroglie's wave model for electrons
  • Know what experiment caused deBroglie to be awarded the Nobel prize for his theory
  • Realize that electrons can exhibit the same type of interference as light in a Young's double slit experiment -- if the wavelengths are the same
  • Know what is meant by a probability wave (also know as a matter wave)
  • Realize that the possible wave functions for a "particle in a box" are just the standing waves of a stretched string
  • Understand that the probability of finding a particle represented by a matter wave is proportional to the wave function squared
  • Be able to state the Pauli exclusion principle and to understand that it applies to electrons, neutrons and protons but not to photons
  • Know that each electron in a atom can be desribed by listing its 4 quantum numbers.   You do not need to worry about the details of the numbers.
  • Recognize that all of the elements in the periodic table are grouped according to their quantum numbers.
  • Be able to discuss in detail the Heisenberg uncertainty principle
  • Be able to discuss the effect of the uncertainty principle on deterministic philosophy
  • Start thinking about how quantum physics has changed the worldview during this century.
Homework
  • Chapter 23 Questions:  31, 35, 36, 37, 41, 43, 45, 50, 57
  • Chapter 23 Exercises:  7, 11, 12
  • Chapter 24 Questions:  7, 11, 17, 19, 22, 23, 24, 31, 33, 39, 44, 53